It's always been like that though. It happens immediately after each wave of accounts is banned, as the botters try to get their new accounts back up to level with their old ones. I think they farm those mobs in central thanalan from underground, until they can queue for dungeons where they do the same thing away from human eyes. Eventually they get to the point they can queue up for amdapor keep normal, where they spam the first hallway repeatedly, as the above icongraph suggests. (Hippogryph skin and bone chips are the only items that drop in that stretch up to the first boss).
No clue what they do after that, but you know SE doesn't care when they publicly release a census that gives more of a window into the lives of bots than it does into the lives of human players.
Edit: you want to see something funny? (I mean "funny" as in, "this clown tastes funny".) Go to Western Thanalan immediately after a major wave of RMT bans. You'll see the walls where level 5 mining nodes are flashing with the light of a thousand pick axes striking paydirt. Those are RMT mining bots, busily leveling their new accounts from inside the rock wall where human players can't see their names to report them. The only indication that they are there are the brilliant flashes of light and "tink tink" sounds of their pickaxes.
